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Relay Principles and Applications

Relay Principles and Applications Working Principle When the coil is energized, it generates a magnetic field that attracts the armature and moves the contacts.…

About 5 min read beginner
RelayControlContactsSwitching

Relay Principles and Applications

Working Principle

When the coil is energized, it generates a magnetic field that attracts the armature and moves the contacts.

Types

Electromagnetic Relay

  • Simple structure
  • Large contact capacity
  • Low cost

    • Solid State Relay (SSR)

  • No contacts
  • Long lifespan
  • Fast speed

    • Time Relay

  • Delayed action
  • Adjustable time

    • Main Parameters

    ParameterDescription
    Coil voltageOperating voltage
    Contact capacityMaximum current/voltage
    Contact typeNO/NC/Changeover
    Pull-in timeAction response time

    Contact Symbols

  • NO: Normally Open
  • NC: Normally Closed
  • COM: Common terminal
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